Birth Sex Ratios in Sheep Over 10 Lambing Seasons: Year 10, the Effects of Litter Size, Seasonal Factors and Ageing

References

• Barash , D. P. 1982 . Sociobiology and behavior , 2nd , Kent , U.K : Hodder and Stoughton .
   Google Scholar
• Bouissou , M.-. F. 1972 . Influence of body weight and presence of horns on social rank in domestic cattle . Animal Behaviour , 20 : 474 – 477 .
   Web of Science ®Google Scholar
• Charnov , E. L. 1985 . “ Natural selection and the evolutionary ecology of sex allocation ” . In Evolution: Essays in honour of John Maynard Smith , Edited by: Greenwood , P. J. , Harvey , P. H. and Slatkin , M. 269 – 285 . Cambridge , U.K : Cambridge University Press .
   Google Scholar
• Charnov , E. L. 1993 . Life history invariants: Some explorations of symmetry in evolutionary ecology , NY : Oxford University Press .
   Google Scholar
• Clutton-Brock , T. H. 1985 . “ Birth sex ratios and the reproductive success of sons and daughters ” . In Evolution: Essays in honour of John Maynard Smith , Edited by: Greenwood , P. J. , Harvey , P. H. and Slatkin , M. 221 – 235 . Cambridge , U.K : Cambridge University Press .
   Google Scholar
• Clutton-Brock , T. H. and Albon , S. D. 1982 . “ Parental investment in male and female offspring in mammals. In King's College Sociobiology Group, Cambridge ” . In Current problems in sociobiology , 223 – 247 . Cambridge , U.K : Cambridge University Press .
   Google Scholar
• Clutton-Brock , T. H. , Albon , S. D. and Guinness , F. E. 1984 . Maternal dominance, breeding success and birth sex ratio in red deer . Nature , 308 : 358 – 360 .
   Web of Science ®Google Scholar
• Clutton-Brock , T. H. , Albon , S. D. and Guinness , F. E. 1988 . “ Reproductive success in male and female red deer ” . In Reproductive success , Edited by: Clutton-Brock , T. H. 325 – 343 . Chicago : University of Chicago Press .
   Google Scholar
• Clutton-Brock , T. H. and Iason , G. R. 1986 . Sex ratio variation in mammals . Quarterly Review of Biology , 61 : 339 – 374 .
   PubMed Web of Science ®Google Scholar
• Collis , K. A. 1976 . An investigation into the factors relating to the dominance order of a herd of dairy cows of similar age and breed . Applied Animal Ethology , 2 : 167 – 173 .
   Google Scholar
• Coulson , J. C. and Hickling , G. 1961 . Variation in the secondary sex-ratio of the Grey Seal Halichoerus grypus (Fab.) during the breeding season . Nature , 190 : 281
   Web of Science ®Google Scholar
• Crews , D. 1994 . “ Constraints on parthenogenesis ” . In The differences between the sexes , Edited by: Short , R. V. and Balaban , E. 23 – 49 . Cambridge , U.K : Cambridge University Press .
   Google Scholar
• Festa-Bianchet , M. , Jorgenson , J. T. and Wishart , W. D. 1992 . Early weaning in bighorn sheep, Ovis canadensis, affects growth of males but not of females . Behavioural Ecology , 5 : 21 – 27 .
   Web of Science ®Google Scholar
• Fisher , R. A. 1930 . The genetical theory of natural selection , Oxford , U.K : Clarendon Press . Reprinted by Dover Publications, New York, 1958
   Google Scholar
• Geist , V. 1971 . Mountain sheep: A study in behaviour and evolution , Chicago , U.S.A : The University of Chicago Press .
   Google Scholar
• Hanrahan , J. P. 1981 . Lamb survival as a function of litter size , Dublin , Ireland : An Foras Taluntais The Agricultural Institute .
   Google Scholar
• Haqq , C. M. , King , C. Y. , Ukiyama , E. , Falsafi , S. , Haqq , T. N. , Donahoe , P. K. and Weiss , M. A. 1994 . Molecular basis of mammalian sexual determination: Activation of Müllerian inhibiting substance gene expression by SRY . Science , 266 : 1494 – 1500 .
   PubMed Web of Science ®Google Scholar
• Huck , U. W. , Pratt , N. C. , Labov , J. B. and Lisk , R. D. 1988 . Effects of age and parity on litter size and offspring sex ratio in golden hamsters (Mesocricetus auratus) . Journal of Reproduction and Fertility , 83 : 209 – 214 .
   Google Scholar
• Hulet , C. V. , Alexander , G. and Hafez , E. S. E. 1975 . “ The behaviour of sheep ” . In The behaviour of domestic animals , Edited by: Hafez , E. S. E. 246 – 295 . London , U.K : Bailiäre Tindall .
   Google Scholar
• Hulet , C. V. , Ercanbrack , S. K. , Blackwell , R. L. , Price , D. A. and Wilson , L. O. 1962 . Mating behaviour in the ram in the multiple sire pen . Journal of Animal Science , 21 : 865 – 869 .
   Web of Science ®Google Scholar
• Hunter , R. H. F. 1995 . Sex determination, differentiation, and intersexuality in placental mammals , Cambridge , U.K : Cambridge University Press .
   Google Scholar
• James , W. 1987a . The human sex ratio. Part 1: A review of the literature . Human Biology , 59 : 721 – 752 .
   PubMed Web of Science ®Google Scholar
• James , W. H. 1987b . The human sex ratio. Part 2: A hypothesis and a program of research . Human Biology , 59 : 873 – 900 .
   PubMed Web of Science ®Google Scholar
• Kent , J. P. 1992 . Birth sex ratios in sheep over six lambing seasons . Behavioural Ecology and Sociobiology , 30 : 151 – 155 .
   Web of Science ®Google Scholar
• Kent , J. P. 1995 . Birth sex ratios in sheep over nine lambing seasons: Years seven to nine and the effects of ageing . Behavioural Ecology and Sociobiology , 35 : 101 – 104 .
   Google Scholar
• Krackow , S. 1995 . Potential mechanisms for sex ratio adjustment in mammals and birds . Biological Reviews , 70 : 225 – 241 .
   PubMed Web of Science ®Google Scholar
• Lynch , J. J. , Hinch , G. N. and Adams , D. B. 1992 . The behaviour of sheep: Biological principles and implications for production , Oxon , U.K : C.A.B International also published by CSIRO Publications, Australia .
   Google Scholar
• Maynard Smith , J. 1982 . “ Introduction. In King's College Sociobiology Group, Cambridge ” . In Current problems in sociobiology , 1 – 3 . Cambridge , U.K : Cambridge University Press .
   Google Scholar
• Moore , N. P. , Kelly , P. F. , Cahill , J. P. and Hayden , T. J. 1995 . Mating strategies and mating success of fallow (Dama dama) bucks in a non-lekking population . Behavioral Ecology and Sociobiology , 36 : 91 – 100 .
   Web of Science ®Google Scholar
• Owens , J. L. , Bindon , B. M. , Edey , T. N. and Piper , L. R. 1985 . Behaviour at parturition and lamb survival of Booroola Merino sheep . Livestock Production and Science , 13 : 359 – 372 .
   Web of Science ®Google Scholar
• Pieau , C. , Girondot , M. , Desvages , G. , Dorizzi , M. , Richard-Mercier , N. and P , Zaborski. 1994 . “ Environmental control of gonadal differentiation ” . In The differences between the sexes , Edited by: Short , R. V. and Balaban , E. 433 – 448 . Cambridge , U.K : Cambridge University Press .
   Google Scholar
• Pollard , I. 1994 . A guide to reproduction: Social issues and human concerns , Cambridge , U.K : Cambridge University Press .
   Google Scholar
• Schein , M. W. and Fohrman , M. H. 1955 . Social dominance relationships in a herd of dairy cattle . British Journal of Animal Behaviour , 3 : 45 – 55 .
   Google Scholar
• Sokal , R. R. and Rohlf , F. J. 1969 . Biometry: The principles and practice of statistics in biological research , San Francisco , U.S.A : Freeman .
   Google Scholar
• Stirling , I. 1971 . Variation in sex ratio of newborn Waddell Seals during the pupping season . Journal of Mammology , 52 : 842 – 844 .
   Web of Science ®Google Scholar
• Trivers , R. 1985 . Social evolution , Menlo Park , California U.S.A : The Benjamin/Cummings Publishing Company, Inc .
   Google Scholar
• Trivers , R. L. and Willard , D. E. 1973 . Natural selection of parental ability to vary the sex ratio of offspring . Science , 179 : 90 – 92 .
   PubMed Web of Science ®Google Scholar
• Williams , G. C. 1979 . The question of adaptive sex ratio in outcrossed verterbrates . Proceedings of the Royal Society (Lond.) (B) , 205 : 567 – 580 .
   PubMed Web of Science ®Google Scholar
• Wilson , J. D. 1994 . “ Translating gonadal sex into phenotypic sex ” . In The differences between the sexes , Edited by: Short , R. V. and Balaban , E. 203 – 212 . Cambridge , U.K : Cambridge University Press .
   Google Scholar